The influence of cyclodextrin on hydrophobicity of pipeline and asphalt distribution: A green and efficient corrosion inhibitor

Abstract

Corrosion inhibitors face significant limitations due to their non-degradability and poor applicability to asphalt systems. The molecular simulation studies show that cyclodextrin (CD) and asphalt can form supramolecular corrosion inhibitors with pipeline hydrophobic modification and corrosion inhibition effects. In particular, the rich hydroxyl structure of CD enables it to stably bind to the pipeline by forming coordination bonds and feedback bonds. When 2 CD molecules are added, the initial wetting time of the emulsion is delayed by 257.81 % compared to Span 80 with the same mass fraction. When 4 CD molecules are added, the emulsion cannot wet the iron surface within the simulation time. Furthermore, the combination of CD and asphalt allows more than 90 % of the asphalt to emulsify and prevent the emulsion from spreading on the pipeline. This results in a synergistic corrosion inhibition effect. These findings suggest that CD-based supramolecular corrosion inhibitors have the potential to be effective and environmentally friendly alternatives to traditional inhibitors in asphalt systems.